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  <div class="section" id="module-html.parser">
<span id="html-parser-simple-html-and-xhtml-parser"></span><h1>20.2. <a class="reference internal" href="#module-html.parser" title="html.parser: A simple parser that can handle HTML and XHTML."><tt class="xref py py-mod docutils literal"><span class="pre">html.parser</span></tt></a> &#8212; Simple HTML and XHTML parser<a class="headerlink" href="#module-html.parser" title="Permalink to this headline">¶</a></h1>
<p id="index-0"><strong>Source code:</strong> <a class="reference external" href="https://hg.python.org/cpython/file/3.4/Lib/html/parser.py">Lib/html/parser.py</a></p>
<hr class="docutils" />
<p>This module defines a class <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> which serves as the basis for
parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML.</p>
<dl class="class">
<dt id="html.parser.HTMLParser">
<em class="property">class </em><tt class="descclassname">html.parser.</tt><tt class="descname">HTMLParser</tt><big>(</big><em>strict=False</em>, <em>*</em>, <em>convert_charrefs=False</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser" title="Permalink to this definition">¶</a></dt>
<dd><p>Create a parser instance.</p>
<p>If <em>convert_charrefs</em> is <tt class="docutils literal"><span class="pre">True</span></tt> (default: <tt class="docutils literal"><span class="pre">False</span></tt>), all character
references (except the ones in <tt class="docutils literal"><span class="pre">script</span></tt>/<tt class="docutils literal"><span class="pre">style</span></tt> elements) are
automatically converted to the corresponding Unicode characters.
The use of <tt class="docutils literal"><span class="pre">convert_charrefs=True</span></tt> is encouraged and will become
the default in Python 3.5.</p>
<p>If <em>strict</em> is <tt class="docutils literal"><span class="pre">False</span></tt> (the default), the parser will accept and parse
invalid markup.  If <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt> the parser will raise an
<a class="reference internal" href="#html.parser.HTMLParseError" title="html.parser.HTMLParseError"><tt class="xref py py-exc docutils literal"><span class="pre">HTMLParseError</span></tt></a> exception instead <a class="footnote-reference" href="#id2" id="id1">[1]</a> when it&#8217;s not
able to parse the markup.  The use of <tt class="docutils literal"><span class="pre">strict=True</span></tt> is discouraged and
the <em>strict</em> argument is deprecated.</p>
<p>An <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> instance is fed HTML data and calls handler methods
when start tags, end tags, text, comments, and other markup elements are
encountered.  The user should subclass <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> and override its
methods to implement the desired behavior.</p>
<p>This parser does not check that end tags match start tags or call the end-tag
handler for elements which are closed implicitly by closing an outer element.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.2: </span><em>strict</em> argument added.</p>
</div>
<div class="deprecated-removed">
<p><span class="versionmodified">Deprecated since version 3.3, will be removed in version 3.5: </span>The <em>strict</em> argument and the strict mode have been deprecated.
The parser is now able to accept and parse invalid markup too.</p>
</div>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span><em>convert_charrefs</em> keyword argument added.</p>
</div>
</dd></dl>

<p>An exception is defined as well:</p>
<dl class="exception">
<dt id="html.parser.HTMLParseError">
<em class="property">exception </em><tt class="descclassname">html.parser.</tt><tt class="descname">HTMLParseError</tt><a class="headerlink" href="#html.parser.HTMLParseError" title="Permalink to this definition">¶</a></dt>
<dd><p>Exception raised by the <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class when it encounters an error
while parsing and <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt>.  This exception provides three
attributes: <tt class="xref py py-attr docutils literal"><span class="pre">msg</span></tt> is a brief message explaining the error,
<tt class="xref py py-attr docutils literal"><span class="pre">lineno</span></tt> is the number of the line on which the broken construct was
detected, and <tt class="xref py py-attr docutils literal"><span class="pre">offset</span></tt> is the number of characters into the line at
which the construct starts.</p>
<div class="deprecated-removed">
<p><span class="versionmodified">Deprecated since version 3.3, will be removed in version 3.5: </span>This exception has been deprecated because it&#8217;s never raised by the parser
(when the default non-strict mode is used).</p>
</div>
</dd></dl>

<div class="section" id="example-html-parser-application">
<h2>20.2.1. Example HTML Parser Application<a class="headerlink" href="#example-html-parser-application" title="Permalink to this headline">¶</a></h2>
<p>As a basic example, below is a simple HTML parser that uses the
<a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class to print out start tags, end tags, and data
as they are encountered:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>

<span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">handle_starttag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Encountered a start tag:&quot;</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_endtag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Encountered an end tag :&quot;</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Encountered some data  :&quot;</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>

<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
<span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;html&gt;&lt;head&gt;&lt;title&gt;Test&lt;/title&gt;&lt;/head&gt;&#39;</span>
            <span class="s">&#39;&lt;body&gt;&lt;h1&gt;Parse me!&lt;/h1&gt;&lt;/body&gt;&lt;/html&gt;&#39;</span><span class="p">)</span>
</pre></div>
</div>
<p>The output will then be:</p>
<div class="highlight-python3"><div class="highlight"><pre>Encountered a start tag: html
Encountered a start tag: head
Encountered a start tag: title
Encountered some data  : Test
Encountered an end tag : title
Encountered an end tag : head
Encountered a start tag: body
Encountered a start tag: h1
Encountered some data  : Parse me!
Encountered an end tag : h1
Encountered an end tag : body
Encountered an end tag : html
</pre></div>
</div>
</div>
<div class="section" id="htmlparser-methods">
<h2>20.2.2. <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> Methods<a class="headerlink" href="#htmlparser-methods" title="Permalink to this headline">¶</a></h2>
<p><a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> instances have the following methods:</p>
<dl class="method">
<dt id="html.parser.HTMLParser.feed">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">feed</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.feed" title="Permalink to this definition">¶</a></dt>
<dd><p>Feed some text to the parser.  It is processed insofar as it consists of
complete elements; incomplete data is buffered until more data is fed or
<a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><tt class="xref py py-meth docutils literal"><span class="pre">close()</span></tt></a> is called.  <em>data</em> must be <a class="reference internal" href="stdtypes.html#str" title="str"><tt class="xref py py-class docutils literal"><span class="pre">str</span></tt></a>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.close">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">close</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.close" title="Permalink to this definition">¶</a></dt>
<dd><p>Force processing of all buffered data as if it were followed by an end-of-file
mark.  This method may be redefined by a derived class to define additional
processing at the end of the input, but the redefined version should always call
the <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> base class method <a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><tt class="xref py py-meth docutils literal"><span class="pre">close()</span></tt></a>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.reset">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">reset</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.reset" title="Permalink to this definition">¶</a></dt>
<dd><p>Reset the instance.  Loses all unprocessed data.  This is called implicitly at
instantiation time.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.getpos">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">getpos</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.getpos" title="Permalink to this definition">¶</a></dt>
<dd><p>Return current line number and offset.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.get_starttag_text">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">get_starttag_text</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.get_starttag_text" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the text of the most recently opened start tag.  This should not normally
be needed for structured processing, but may be useful in dealing with HTML &#8220;as
deployed&#8221; or for re-generating input with minimal changes (whitespace between
attributes can be preserved, etc.).</p>
</dd></dl>

<p>The following methods are called when data or markup elements are encountered
and they are meant to be overridden in a subclass.  The base class
implementations do nothing (except for <a class="reference internal" href="#html.parser.HTMLParser.handle_startendtag" title="html.parser.HTMLParser.handle_startendtag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_startendtag()</span></tt></a>):</p>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_starttag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_starttag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_starttag" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle the start of a tag (e.g. <tt class="docutils literal"><span class="pre">&lt;div</span> <span class="pre">id=&quot;main&quot;&gt;</span></tt>).</p>
<p>The <em>tag</em> argument is the name of the tag converted to lower case. The <em>attrs</em>
argument is a list of <tt class="docutils literal"><span class="pre">(name,</span> <span class="pre">value)</span></tt> pairs containing the attributes found
inside the tag&#8217;s <tt class="docutils literal"><span class="pre">&lt;&gt;</span></tt> brackets.  The <em>name</em> will be translated to lower case,
and quotes in the <em>value</em> have been removed, and character and entity references
have been replaced.</p>
<p>For instance, for the tag <tt class="docutils literal"><span class="pre">&lt;A</span> <span class="pre">HREF=&quot;http://www.cwi.nl/&quot;&gt;</span></tt>, this method
would be called as <tt class="docutils literal"><span class="pre">handle_starttag('a',</span> <span class="pre">[('href',</span> <span class="pre">'http://www.cwi.nl/')])</span></tt>.</p>
<p>All entity references from <a class="reference internal" href="html.entities.html#module-html.entities" title="html.entities: Definitions of HTML general entities."><tt class="xref py py-mod docutils literal"><span class="pre">html.entities</span></tt></a> are replaced in the attribute
values.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_endtag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_endtag</tt><big>(</big><em>tag</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_endtag" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle the end tag of an element (e.g. <tt class="docutils literal"><span class="pre">&lt;/div&gt;</span></tt>).</p>
<p>The <em>tag</em> argument is the name of the tag converted to lower case.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_startendtag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_startendtag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_startendtag" title="Permalink to this definition">¶</a></dt>
<dd><p>Similar to <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_starttag()</span></tt></a>, but called when the parser encounters an
XHTML-style empty tag (<tt class="docutils literal"><span class="pre">&lt;img</span> <span class="pre">...</span> <span class="pre">/&gt;</span></tt>).  This method may be overridden by
subclasses which require this particular lexical information; the default
implementation simply calls <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_starttag()</span></tt></a> and <a class="reference internal" href="#html.parser.HTMLParser.handle_endtag" title="html.parser.HTMLParser.handle_endtag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_endtag()</span></tt></a>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_data">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_data</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_data" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process arbitrary data (e.g. text nodes and the
content of <tt class="docutils literal"><span class="pre">&lt;script&gt;...&lt;/script&gt;</span></tt> and <tt class="docutils literal"><span class="pre">&lt;style&gt;...&lt;/style&gt;</span></tt>).</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_entityref">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_entityref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_entityref" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process a named character reference of the form
<tt class="docutils literal"><span class="pre">&amp;name;</span></tt> (e.g. <tt class="docutils literal"><span class="pre">&amp;gt;</span></tt>), where <em>name</em> is a general entity reference
(e.g. <tt class="docutils literal"><span class="pre">'gt'</span></tt>).  This method is never called if <em>convert_charrefs</em> is
<tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_charref">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_charref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_charref" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process decimal and hexadecimal numeric character
references of the form <tt class="docutils literal"><span class="pre">&amp;#NNN;</span></tt> and <tt class="docutils literal"><span class="pre">&amp;#xNNN;</span></tt>.  For example, the decimal
equivalent for <tt class="docutils literal"><span class="pre">&amp;gt;</span></tt> is <tt class="docutils literal"><span class="pre">&amp;#62;</span></tt>, whereas the hexadecimal is <tt class="docutils literal"><span class="pre">&amp;#x3E;</span></tt>;
in this case the method will receive <tt class="docutils literal"><span class="pre">'62'</span></tt> or <tt class="docutils literal"><span class="pre">'x3E'</span></tt>.  This method
is never called if <em>convert_charrefs</em> is <tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_comment">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_comment</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_comment" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called when a comment is encountered (e.g. <tt class="docutils literal"><span class="pre">&lt;!--comment--&gt;</span></tt>).</p>
<p>For example, the comment <tt class="docutils literal"><span class="pre">&lt;!--</span> <span class="pre">comment</span> <span class="pre">--&gt;</span></tt> will cause this method to be
called with the argument <tt class="docutils literal"><span class="pre">'</span> <span class="pre">comment</span> <span class="pre">'</span></tt>.</p>
<p>The content of Internet Explorer conditional comments (condcoms) will also be
sent to this method, so, for <tt class="docutils literal"><span class="pre">&lt;!--[if</span> <span class="pre">IE</span> <span class="pre">9]&gt;IE9-specific</span> <span class="pre">content&lt;![endif]--&gt;</span></tt>,
this method will receive <tt class="docutils literal"><span class="pre">'[if</span> <span class="pre">IE</span> <span class="pre">9]&gt;IE9-specific</span> <span class="pre">content&lt;![endif]'</span></tt>.</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_decl">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_decl</tt><big>(</big><em>decl</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_decl" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle an HTML doctype declaration (e.g.
<tt class="docutils literal"><span class="pre">&lt;!DOCTYPE</span> <span class="pre">html&gt;</span></tt>).</p>
<p>The <em>decl</em> parameter will be the entire contents of the declaration inside
the <tt class="docutils literal"><span class="pre">&lt;!...&gt;</span></tt> markup (e.g. <tt class="docutils literal"><span class="pre">'DOCTYPE</span> <span class="pre">html'</span></tt>).</p>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.handle_pi">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_pi</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_pi" title="Permalink to this definition">¶</a></dt>
<dd><p>Method called when a processing instruction is encountered.  The <em>data</em>
parameter will contain the entire processing instruction. For example, for the
processing instruction <tt class="docutils literal"><span class="pre">&lt;?proc</span> <span class="pre">color='red'&gt;</span></tt>, this method would be called as
<tt class="docutils literal"><span class="pre">handle_pi(&quot;proc</span> <span class="pre">color='red'&quot;)</span></tt>.  It is intended to be overridden by a derived
class; the base class implementation does nothing.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class uses the SGML syntactic rules for processing
instructions.  An XHTML processing instruction using the trailing <tt class="docutils literal"><span class="pre">'?'</span></tt> will
cause the <tt class="docutils literal"><span class="pre">'?'</span></tt> to be included in <em>data</em>.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="html.parser.HTMLParser.unknown_decl">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">unknown_decl</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.unknown_decl" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called when an unrecognized declaration is read by the parser.</p>
<p>The <em>data</em> parameter will be the entire contents of the declaration inside
the <tt class="docutils literal"><span class="pre">&lt;![...]&gt;</span></tt> markup.  It is sometimes useful to be overridden by a
derived class.  The base class implementation raises an <a class="reference internal" href="#html.parser.HTMLParseError" title="html.parser.HTMLParseError"><tt class="xref py py-exc docutils literal"><span class="pre">HTMLParseError</span></tt></a>
when <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>

</div>
<div class="section" id="examples">
<span id="htmlparser-examples"></span><h2>20.2.3. Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
<p>The following class implements a parser that will be used to illustrate more
examples:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>
<span class="kn">from</span> <span class="nn">html.entities</span> <span class="k">import</span> <span class="n">name2codepoint</span>

<span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span>
    <span class="k">def</span> <span class="nf">handle_starttag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Start tag:&quot;</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
        <span class="k">for</span> <span class="n">attr</span> <span class="ow">in</span> <span class="n">attrs</span><span class="p">:</span>
            <span class="nb">print</span><span class="p">(</span><span class="s">&quot;     attr:&quot;</span><span class="p">,</span> <span class="n">attr</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_endtag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;End tag  :&quot;</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Data     :&quot;</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_comment</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Comment  :&quot;</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_entityref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
        <span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="n">name2codepoint</span><span class="p">[</span><span class="n">name</span><span class="p">])</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Named ent:&quot;</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_charref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
        <span class="k">if</span> <span class="n">name</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s">&#39;x&#39;</span><span class="p">):</span>
            <span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">[</span><span class="mi">1</span><span class="p">:],</span> <span class="mi">16</span><span class="p">))</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">))</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Num ent  :&quot;</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
    <span class="k">def</span> <span class="nf">handle_decl</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
        <span class="nb">print</span><span class="p">(</span><span class="s">&quot;Decl     :&quot;</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>

<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
</pre></div>
</div>
<p>Parsing a doctype:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;!DOCTYPE HTML PUBLIC &quot;-//W3C//DTD HTML 4.01//EN&quot; &#39;</span>
<span class="gp">... </span>            <span class="s">&#39;&quot;http://www.w3.org/TR/html4/strict.dtd&quot;&gt;&#39;</span><span class="p">)</span>
<span class="go">Decl     : DOCTYPE HTML PUBLIC &quot;-//W3C//DTD HTML 4.01//EN&quot; &quot;http://www.w3.org/TR/html4/strict.dtd&quot;</span>
</pre></div>
</div>
<p>Parsing an element with a few attributes and a title:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;img src=&quot;python-logo.png&quot; alt=&quot;The Python logo&quot;&gt;&#39;</span><span class="p">)</span>
<span class="go">Start tag: img</span>
<span class="go">     attr: (&#39;src&#39;, &#39;python-logo.png&#39;)</span>
<span class="go">     attr: (&#39;alt&#39;, &#39;The Python logo&#39;)</span>
<span class="go">&gt;&gt;&gt;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;h1&gt;Python&lt;/h1&gt;&#39;</span><span class="p">)</span>
<span class="go">Start tag: h1</span>
<span class="go">Data     : Python</span>
<span class="go">End tag  : h1</span>
</pre></div>
</div>
<p>The content of <tt class="docutils literal"><span class="pre">script</span></tt> and <tt class="docutils literal"><span class="pre">style</span></tt> elements is returned as is, without
further parsing:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;style type=&quot;text/css&quot;&gt;#python { color: green }&lt;/style&gt;&#39;</span><span class="p">)</span>
<span class="go">Start tag: style</span>
<span class="go">     attr: (&#39;type&#39;, &#39;text/css&#39;)</span>
<span class="go">Data     : #python { color: green }</span>
<span class="go">End tag  : style</span>
<span class="go">&gt;&gt;&gt;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;script type=&quot;text/javascript&quot;&gt;&#39;</span>
<span class="gp">... </span>            <span class="s">&#39;alert(&quot;&lt;strong&gt;hello!&lt;/strong&gt;&quot;);&lt;/script&gt;&#39;</span><span class="p">)</span>
<span class="go">Start tag: script</span>
<span class="go">     attr: (&#39;type&#39;, &#39;text/javascript&#39;)</span>
<span class="go">Data     : alert(&quot;&lt;strong&gt;hello!&lt;/strong&gt;&quot;);</span>
<span class="go">End tag  : script</span>
</pre></div>
</div>
<p>Parsing comments:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;!-- a comment --&gt;&#39;</span>
<span class="gp">... </span>            <span class="s">&#39;&lt;!--[if IE 9]&gt;IE-specific content&lt;![endif]--&gt;&#39;</span><span class="p">)</span>
<span class="go">Comment  :  a comment</span>
<span class="go">Comment  : [if IE 9]&gt;IE-specific content&lt;![endif]</span>
</pre></div>
</div>
<p>Parsing named and numeric character references and converting them to the
correct char (note: these 3 references are all equivalent to <tt class="docutils literal"><span class="pre">'&gt;'</span></tt>):</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&amp;gt;&amp;#62;&amp;#x3E;&#39;</span><span class="p">)</span>
<span class="go">Named ent: &gt;</span>
<span class="go">Num ent  : &gt;</span>
<span class="go">Num ent  : &gt;</span>
</pre></div>
</div>
<p>Feeding incomplete chunks to <a class="reference internal" href="#html.parser.HTMLParser.feed" title="html.parser.HTMLParser.feed"><tt class="xref py py-meth docutils literal"><span class="pre">feed()</span></tt></a> works, but
<a class="reference internal" href="#html.parser.HTMLParser.handle_data" title="html.parser.HTMLParser.handle_data"><tt class="xref py py-meth docutils literal"><span class="pre">handle_data()</span></tt></a> might be called more than once
(unless <em>convert_charrefs</em> is set to <tt class="docutils literal"><span class="pre">True</span></tt>):</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">for</span> <span class="n">chunk</span> <span class="ow">in</span> <span class="p">[</span><span class="s">&#39;&lt;sp&#39;</span><span class="p">,</span> <span class="s">&#39;an&gt;buff&#39;</span><span class="p">,</span> <span class="s">&#39;ered &#39;</span><span class="p">,</span> <span class="s">&#39;text&lt;/s&#39;</span><span class="p">,</span> <span class="s">&#39;pan&gt;&#39;</span><span class="p">]:</span>
<span class="gp">... </span>    <span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="n">chunk</span><span class="p">)</span>
<span class="gp">...</span>
<span class="go">Start tag: span</span>
<span class="go">Data     : buff</span>
<span class="go">Data     : ered</span>
<span class="go">Data     : text</span>
<span class="go">End tag  : span</span>
</pre></div>
</div>
<p>Parsing invalid HTML (e.g. unquoted attributes) also works:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">&#39;&lt;p&gt;&lt;a class=link href=#main&gt;tag soup&lt;/p &gt;&lt;/a&gt;&#39;</span><span class="p">)</span>
<span class="go">Start tag: p</span>
<span class="go">Start tag: a</span>
<span class="go">     attr: (&#39;class&#39;, &#39;link&#39;)</span>
<span class="go">     attr: (&#39;href&#39;, &#39;#main&#39;)</span>
<span class="go">Data     : tag soup</span>
<span class="go">End tag  : p</span>
<span class="go">End tag  : a</span>
</pre></div>
</div>
<p class="rubric">Footnotes</p>
<table class="docutils footnote" frame="void" id="id2" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id1">[1]</a></td><td>For backward compatibility reasons <em>strict</em> mode does not raise
exceptions for all non-compliant HTML.  That is, some invalid HTML
is tolerated even in <em>strict</em> mode.</td></tr>
</tbody>
</table>
</div>
</div>


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  <ul>
<li><a class="reference internal" href="#">20.2. <tt class="docutils literal"><span class="pre">html.parser</span></tt> &#8212; Simple HTML and XHTML parser</a><ul>
<li><a class="reference internal" href="#example-html-parser-application">20.2.1. Example HTML Parser Application</a></li>
<li><a class="reference internal" href="#htmlparser-methods">20.2.2. <tt class="docutils literal"><span class="pre">HTMLParser</span></tt> Methods</a></li>
<li><a class="reference internal" href="#examples">20.2.3. Examples</a></li>
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